JP2013139348A - Fast curing composition, mortar and concrete - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide mortar and concrete excellent in fast curing property, waterproofing property, and work efficiency in a waterproofing work or the like, hardly generating a crack, and having high compressive strength, bending strength, bending toughness or the like, and to provide a fast curing composition used therefor.SOLUTION: This fast curing composition to be provided contains following components (A)-(G): (A) a fast curing admixture containing at least one kind or more of inorganic salts selected from alkali metal carbonates, alkali metal sulfates, alkaline earth metal carbonates and alkaline earth metal sulfates, and calcium aluminates, (B) portland cement, (C) a setting modifier, (D) a water reducing agent, (E) organic fibers, (F) a resin containing a polymer of an acrylic ester and/or a resin containing a copolymer of an acrylic ester and styrene, and (G) water.

Description

  The present invention relates to mortar and concrete having high compressive strength, bending strength, bending toughness, and the like, and a fast-curing composition used for these.

Concrete floor slabs installed on bridges and the like are subject to repeated load from vehicles passing over the bridge and are likely to crack, so periodic repairs are necessary. One of the repair methods is an upper surface thickening method. This method is to cut the upper surface of the existing floorboard by about 10 mm, and then add concrete to increase the resistance cross section, and to restore and improve the load bearing capacity. The main flow of the work is cutting of asphalt road surface → Concrete surface cutting work → Concrete work → Waterproof work → Pavement work.
The concrete used for this construction method is i) high compressive strength and bending strength, ii) fast hardening for early release of traffic, iii) low drying shrinkage strain, iv) completely integrated old and new concrete It is required that Therefore, as the concrete satisfying the required performance, generally fast-hardening concrete mixed with steel fibers is used. By the way, in the “Upper surface pressure boosting method design and construction manual” published by the Highway Research Committee, the concrete has a compressive strength of 3 N hours after kneading is defined as 24 N / mm ² or more. The concrete is desired to have a bending strength of 4.5 N / mm ² or more in 3 hours after kneading.

And as this concrete composition, for example, in Patent Document 1, a clinker containing 3CaO · SiO ₂ solid solution and 11CaO · 7Al ₂ O ₃ · CaF ₂ , anhydrous gypsum, calcium aluminosilicate glass, ground granulated blast furnace slag, There has been proposed a concrete composition of ultrafast cement containing a high-performance water reducing agent, a setting modifier, steel fibers having a specific tensile strength, and the like.
However, although the steel fibers increase the bending strength and bending toughness of the concrete, the concrete becomes heavy, and the steel fibers protruding from the concrete surface by the cutting work hinder the waterproofing work. Moreover, since the concrete has insufficient waterproofness, the steel fibers are easily rusted. In particular, in snowy areas, rusting of steel fibers is significantly accelerated by the snow melting agent that is sown on the road in winter.

JP 2007-320833 A

  Therefore, the present invention is a mortar and concrete (hereinafter referred to as “concrete etc.”) that are excellent in workability such as quick hardening, waterproofness and waterproofing work, and have high bending strength and bending toughness without using steel fibers. An object of the present invention is to provide a fast-curing composition used for these.

  As a result of intensive studies on a quick-curing composition suitable for the above-mentioned purpose, the present inventor found that a fast-curing composition containing the following component [1] can achieve the above-mentioned object and completed the present invention.

That is, the present invention provides the following [1] to [4].
[1] A fast-curing composition containing the following components (A) to (G).
(A) A fast-setting admixture containing at least one inorganic salt selected from alkali metal carbonates, alkali metal sulfates, alkaline earth metal carbonates, and alkaline earth metal sulfates, and calcium aluminates (B) Portland cement (C) Setting modifier (D) Water reducing agent (E) Organic fiber (F) Resin containing a polymer of acrylic ester and / or resin containing a copolymer of acrylic ester and styrene (G )water

[2] The fast-curing composition according to [1], further including an antifoaming agent and / or a shrinkage reducing agent.
[3] A mortar containing the quick-hardening composition according to any one of [1] or [2] and a fine aggregate.
[4] Concrete including the mortar according to [3] and coarse aggregate.

Concrete or the like using the fast-curing composition of the present invention is excellent in workability such as fast-curing, waterproofing, and waterproofing work, is not easily cracked, and is excellent in compressive strength, bending strength, bending toughness, and the like. .
In addition, the said quick hardening means the performance which expresses the compressive strength (24 N / mm < ² > or more) prescribed | regulated to the said manual.

As described above, the fast-curing composition of the present invention comprises (A) a fast-curing admixture, (B) Portland cement, (C) a setting modifier, (D) a water reducing agent, (E) an organic fiber, and (F) an acrylic. A resin containing an acid ester polymer and / or a resin containing a copolymer of an acrylate ester and styrene, and (G) water.
The present invention is described in detail below.

(A) Fast-hardening admixture As described above, the admixture includes i) calcium aluminate, ii) alkali metal carbonate, iii) alkali metal sulfate, vi) alkaline earth metal carbonate, and v) And at least one inorganic salt selected from alkaline earth metal sulfates. Hereinafter, each of these components will be described.

i) Calcium aluminate Calcium aluminate is, for example, C ₁₂ A ₇ (12CaO · 7Al ₂ O ₃ ), C ₃ A (3CaO · Al ₂ O ₃ ), C ₁₁ A ₇ · CaF ₂ (11CaO · 7Al). ₂ O ₃ · CaF ₂ ), NC ₈ A ₃ (Na ₂ O · 8CaO · 3Al ₂ O ₃ ), Irwin (3CaO · 3Al ₂ O ₃ · CaSO ₄ ), CA (CaO · Al ₂ O ₃ ), CA ₂ Examples thereof include at least one selected from (CaO · 2Al ₂ O ₃ ) and alumina cement. Among these, CA and alumina cement are preferable because they are particularly excellent in rapid hardening.
Further, the fineness of the calcium aluminates is preferably 4000 cm ² / g or more in Blaine specific surface area, more preferably at least 5000 cm ² / g, still more preferably at least 6000 cm ² / g. If the value is less than 4000 cm ² / g, the rapid hardening may be low. The upper limit of the fineness is 15000 cm ² / g from the viewpoint of cost.

ii) Alkali metal carbonate The carbonate includes at least one selected from lithium carbonate, sodium carbonate, potassium carbonate, lithium hydrogen carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate and the like. Among these, lithium carbonate is preferable because it is excellent in strength development in a short time. The carbonate promotes the hydration reaction of calcium aluminates, and when combined with gypsum, the strength of concrete and the like can be increased in a short time.
Fineness of the carbonate is preferably from 3000 cm ² / g or more in Blaine specific surface area, more preferably at least 4000 cm ² / g, still more preferably at least 5000 cm ² / g. When the value is less than 3000 cm ² / g, strength development in a short time may be low. The upper limit of the fineness is 15000 cm ² / g from the viewpoint of cost.
1-15 mass parts is preferable with respect to 100 mass parts of calcium aluminates, as for the mixture ratio of this carbonate, 3-10 mass parts is more preferable, and 4-8 mass parts is further more preferable. When the value is 1 to 15 parts by mass, strength development in a short time such as concrete is high.

iii) Alkali metal sulfate The sulfate includes at least one selected from lithium sulfate, sodium sulfate, potassium sulfate, lithium hydrogen sulfate, sodium hydrogen sulfate, potassium hydrogen sulfate, and the like. Among these, sodium sulfate is preferable and anhydrous sodium sulfate is more preferable in order to be excellent in the moisture-proofing effect of the fast-curing composition and to stabilize the effect of the water reducing agent.
The average particle size of the sulfate is preferably 100 μm or less, more preferably 5 to 100 μm, and even more preferably 10 to 80 μm. When the value exceeds 100 μm, the moisture-proof effect or the like may be reduced. In addition, the said average particle diameter means the particle diameter which 50 mass% of all the particles measured using the laser particle size distribution measuring apparatus passes.
The blending ratio of the sulfate is preferably 2 to 10 parts by mass, more preferably 3 to 8 parts by mass, and still more preferably 4 to 7 parts by mass with respect to 100 parts by mass of calcium aluminates. If this value is 2-10 mass parts, the moisture-proof effect is high. Furthermore, the blending ratio of the sulfate is preferably 50 to 200 parts by mass, more preferably 70 to 200 parts by mass, and still more preferably 100 to 180 parts by mass with respect to 100 parts by mass of the carbonate. If this value is 50-200 mass parts, the strength expression property in the short time of concrete etc. by the said carbonate will improve.

vi) Alkaline earth metal carbonate The carbonate includes at least one selected from calcium carbonate and magnesium carbonate.
Fineness of the carbonate is preferably from 3000 cm ² / g or more in Blaine specific surface area, more preferably at least 4000 cm ² / g, still more preferably at least 5000 cm ² / g. When the value is less than 3000 cm ² / g, long-term strength elongation may be low. The upper limit of the fineness is 15000 cm ² / g from the viewpoint of cost.
1-10 mass parts is preferable with respect to 100 mass parts of calcium aluminates, as for the mixture ratio of this carbonate, 2-8 mass parts is more preferable, and 3-7 mass parts is further more preferable. If this value is 1-10 mass parts, elongation of long-term strength, such as concrete, is large.

v) Alkaline earth metal sulfate The alkaline earth metal sulfate comprises at least one selected from calcium sulfate, calcium hydrogen sulfate, magnesium sulfate, magnesium hydrogen sulfate, anhydrous gypsum, hemihydrate gypsum, and dihydrate gypsum. Can be mentioned. Among these, gypsum is preferable, anhydrous gypsum is more preferable, and type II anhydrous gypsum is more preferable. As a result of the reaction of gypsum and calcium aluminate to produce ettringite, the strength of concrete or the like increases in a short time. In addition to natural products, gypsum waste such as flue gas desulfurization gypsum, phosphate gypsum, titanium gypsum, hydrofluoric acid gypsum, refined gypsum, and gypsum boat waste can be used.
Fineness of the sulfate is preferably from 4000 cm ² / g or more in Blaine specific surface area, more preferably at least 5000 cm ² / g, still more preferably at least 6000 cm ² / g. When the value is less than 4000 cm ² / g, strength development in a short time may be low. The upper limit of the fineness is 15000 cm ² / g from the viewpoint of cost.
The blending ratio of the sulfate is preferably 20 to 150 parts by mass, more preferably 40 to 120 parts by mass, and still more preferably 50 to 100 parts by mass with respect to 100 parts by mass of calcium aluminates. When the value is 20 to 150 parts by mass, strength development in a short time such as concrete is high.

The blending ratio of the quick-setting admixture is preferably 10 to 100 parts by mass, more preferably 20 to 80 parts by mass, and still more preferably 30 to 60 parts by mass with respect to 100 parts by mass of Portland cement described later.
Examples of commercially available quick-setting admixtures containing the above components include (1) “Facet” (registered trademark) manufactured by Taiheiyo Materials Co., Ltd. and (2) “Denka Cosmic” (registered trademark) manufactured by Denki Kagaku Kogyo Co., Ltd. Can be mentioned.

(B) Portland cement As Portland cement, normal Portland cement, early-strength Portland cement, moderately hot Portland cement, etc. can be used. Portland cement is preferably used.
Fineness of the cement is preferably 3000~5000cm ² / g in Blaine specific surface area, 3100~4600cm ² / g is more preferable. If the value is less than 3000 cm ² / g, short-term strength development may be low. The fineness can be adjusted using a pulverizer such as a ball mill or a rod mill.
When producing concrete in the present invention, the blending amount of Portland cement is preferably 200 to 450 kg / m ³ , more preferably 250 to 400 kg / m ³ per 1 m ^{3 of} concrete.

(C) Coagulation regulator The regulator includes at least one selected from citric acid, gluconic acid, tartaric acid, heptonic acid, and salts thereof. Among these, citric acid, heptonic acid, and salts thereof are preferable because rapid setting can be prevented by suppressing rapid formation of ettringite. Examples of the salt include at least one selected from alkali metal salts such as sodium and potassium and alkaline earth metal salts such as calcium and magnesium.
The blending ratio of the adjusting agent is preferably 0.1 to 3.0 parts by mass with respect to 100 parts by mass of the total amount of Portland cement and fast-curing admixture (hereinafter referred to as “binder”), and 0.2 to 2. 7 mass parts is more preferable, and 0.5-2.5 mass parts is further more preferable. When the value is less than 0.1 parts by mass, the time for which the concrete or the like maintains fluidity is short, and when it exceeds 3.0 parts by mass, the strength may decrease. In addition, the said coagulation regulator can use both the state of a powder and the state melt | dissolved in water.

(D) Water reducing agent Examples of the water reducing agent include at least one selected from polycarboxylic acid, naphthalenesulfonic acid formaldehyde condensate, melamine sulfonic acid formaldehyde condensate, lignin sulfonic acid, and salts thereof. Examples of the salt include at least one selected from alkali metal salts such as sodium and potassium and alkaline earth metal salts such as calcium and magnesium. These water reducing agents are classified into AE water reducing agents, high performance water reducing agents, high performance AE water reducing agents, and the like according to water reducing performance and air entrainment performance. Among these water reducing agents, a high-performance AE water reducing agent mainly composed of a polycarboxylate is preferable because of its excellent water reducing performance and slump retention performance.
The blending ratio of the water reducing agent is preferably 0.1 to 5 parts by mass, more preferably 0.3 to 4 parts by mass, and further preferably 0.5 to 2 parts by mass with respect to 100 parts by mass of the binder. preferable. When the value is 0.1 to 5 parts by mass, it is easy to adjust the setting of concrete or the like, and there is no risk of strength reduction.
The water reducing agent can be used in either a powder state or a state dissolved in water.

(E) Organic fiber The fiber used in the present invention is an organic fiber. Since the concrete of the present invention contains organic fibers, i) low mass per unit volume, ii) high bending strength and bending toughness, iii) low drying shrinkage, iv) easy work such as waterproofing There are advantages such as.
Examples of the fibers used in the present invention include at least one selected from vinylon fibers, aramid fibers, polyethylene fibers, polypropylene fibers, polyvinyl alcohol fibers, and cellulose fibers. Among these, vinylon fibers are preferable because they are inexpensive and can effectively restrain concrete and the like.

The diameter of the fiber is preferably 0.027 to 0.90 mm, more preferably 0.45 to 0.90 mm, and still more preferably 0.50 to 0.70 mm. If the value is less than 0.027 mm, the fluidity of concrete or the like is lowered, and the tensile strength of the fibers is low, so that the fibers are easily cut when subjected to tension. If the value exceeds 0.90 mm, the number of fibers per unit volume of the concrete or the like is decreased. Therefore, the concrete or the like cannot be effectively restrained, and the strength and bending toughness may be reduced.
6-60 mm is preferable and, as for the length of the said fiber, 20-30 mm is more preferable. If the value is less than 6 mm, the concrete or the like may not be effectively restrained, and if it exceeds 60 mm, the fluidity or workability of the concrete may be reduced.
Further, the organic fiber content in the fast-curing composition is preferably 0.3 to 2.0% by volume, more preferably 0.5 to 2.0% by volume, and 0.8 to 1.7% by volume. Further preferred. If the value is less than 0.3% by volume, the bending toughness of concrete or the like may be lowered, and if it exceeds 2.0% by volume, the workability of the concrete or the like may be lowered.

(F) Resin containing a polymer of acrylic ester and / or resin containing a copolymer of acrylic ester and styrene A resin containing a polymer of acrylic ester is a monomer residue of (meth) acrylic ester. It means a resin containing a (co) polymer (excluding a copolymer with styrene) having a content of 50% by mass or more. The resin containing a copolymer of acrylic acid ester and styrene means a resin containing a copolymer having a content of monomer residues of acrylic acid ester and styrene of 50% by mass or more. These resins may be used alone or in combination.

Here, (meth) acrylic acid ester includes methyl (meth) acrylate, ethyl (meth) acrylate, (meth) acrylic acid-n-propyl, (meth) acrylic acid-i-propyl, and the like.
The styrene includes substituted styrene in addition to styrene. Here, as substituted styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2-methoxystyrene, 3-methoxystyrene, and 4-methoxy Examples include monosubstituted styrene such as styrene, and polysubstituted styrene such as 3,4-dimethylstyrene, 3,4-diethylstyrene, and 4-chloro-3-methylstyrene.
The resin may contain a monomer residue copolymerizable with the monomer as another monomer residue.

  The blending ratio of the resin is preferably 2 to 30 parts by mass and more preferably 2.5 to 15.0 parts by mass in terms of solid content with respect to 100 parts by mass of the binder. If the value is outside the range of 2 to 30 parts by mass, the waterproofness, workability, strength development, etc. of concrete and the like may be reduced.

(G) Water The water used in the present invention can be used as long as it does not affect the strength development and fluidity of the fast-curing composition. Examples of such water include tap water, treated sewage water, and supernatant water of ready-mixed concrete.
The mass ratio of water / binder is preferably 0.15 to 0.5, and more preferably 0.3 to 0.45. When the ratio is 0.15 to 0.5, the strength of concrete or the like is high and the fluidity and workability are good.

(H) Fine aggregate Fine aggregate used for the mortar and concrete of the present invention is natural sand such as river sand, mountain sand, sea sand, quartz sand, crushed sand, artificial sand such as blast furnace slag fine aggregate, recycled fine aggregate, And mixtures thereof. The blending ratio of the fine aggregate is preferably 50 to 500 parts by mass, more preferably 100 to 400 parts by mass with respect to 100 parts by mass of the binder. If this value is 50-500 mass parts, there will be little generation | occurrence | production of the crack of a mortar and fluidity | liquidity will be favorable.

(I) Coarse aggregate The coarse aggregate used in the concrete of the present invention includes gravel, crushed stone, recycled coarse aggregate, and a mixture thereof. The particle size of the coarse aggregate is preferably 5 to 25 mm, more preferably 5 to 13 mm. Moreover, 0-500 mass parts is preferable with respect to 100 mass parts of binders, and, as for the mixture ratio of the said coarse aggregate, 100-250 mass parts is more preferable. When the value is 0 to 500 parts by mass, the workability of the concrete is good.

(J) Other components The fast-curing composition of the present invention may further contain admixtures (materials) such as an antifoaming agent, a shrinkage reducing agent, an expansion material, and a hydration heat inhibitor.
Examples of the antifoaming agent include liquid or powdered antifoaming agents such as ester, polyether, mineral oil, and silicone. The blending ratio of the antifoaming agent is preferably 0.04 parts by mass or less and more preferably 0.02 parts by mass or less in terms of solid content with respect to 100 parts by mass of the fast-curing composition. If the value exceeds 0.04 parts by mass, hydration of the fast-curing composition may be inhibited.

Examples of the shrinkage reducing agent include at least one selected from alkylene oxide adducts of lower alcohols, glycol ether / amino alcohol derivatives, polyethers, alkylene oxide copolymers, and mixtures of polyoxyalkylene alcohol ethers and inorganic fillers. The above is mentioned. The blending ratio of the shrinkage reducing agent is preferably 2.0 parts by mass or less, more preferably 0.5 to 1.0 part by mass in terms of solid content with respect to 100 parts by mass of the fast-curing composition. If the value exceeds 2.0 parts by mass, hydration of the fast-curing composition may be inhibited.
Examples of the expansion material include lime-based and calcium sulfoaluminate-based materials.
The mixing ratio of the expansion material is preferably 10 to 40 kg per 1 m ^{3 of} concrete, and more preferably 20 to 30 kg. If the value is less than 10 kg, the expansion amount is low, and if it exceeds 40 kg, the expansion amount may be excessive.

  Examples of the hydration heat inhibitor include at least one selected from dextrin, modified starch, boric acid and the like. The hydration heat inhibitor has an effect of suppressing shrinkage cracking by suppressing the heat of hydration of the fast-curing composition. The blending ratio of the hydration heat inhibitor is preferably 0.01 to 0.3 parts by mass, more preferably 0.05 to 0.2 parts by mass, and 0.1 to 0 parts per 100 parts by mass of the fast-curing composition. .15 is more preferred. When the value is 0.01 to 0.3 parts by mass, the heat of hydration can be suppressed without delaying the setting.

  Moreover, the quick-hardening composition of the present invention may further contain an admixture or a mixture such as fly ash, coal ash, silica fume, and limestone as long as the fast-hardening property is not inhibited.

The method for kneading concrete or the like of the present invention and the kneader are not particularly limited. As a kneading machine, for example, an omni mixer, a pan-type mixer, a biaxial kneading mixer, a tilting cylinder mixer, or the like can be used. The compressive strength of the mortar of the present invention, in 3 hours after kneading becomes 15N / mm ² or more, and compressive strength and flexural strength of the concrete of the present invention, respectively 24N / mm ² or more and 4.5 N / mm ² or more become.
Therefore, the fast-curing composition of the present invention is (super) fast-curing for steel bridges, RC bridges, PC bridges, RC / PC hollow floor slab bridge slabs, etc. And suitable for applications requiring high strength.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples.

1. Materials used (A) Fast-hardening admixture; Trade name “Facet” (manufactured by Taiheiyo Materials Co., Ltd.)
The admixture corresponds to the quick-setting admixture contained in the quick-setting composition of the present invention.
(B) Portland cement;
Ordinary Portland cement (Blaine specific surface area 3200cm ² / g, Taiheiyo Cement)
(C) Setting controller: citric acid (manufactured by Onoda Chemico)
(D) Water reducing agent; trade name “Mighty 150” (registered trademark, manufactured by Kao Corporation)
(E) Organic fiber (E-1) Vinylon fiber A: φ0.20 × 18 mm (manufactured by Kuraray Co., Ltd.)
(E-2) Vinylon fiber B: φ0.66 × 30 mm (manufactured by Kuraray Co., Ltd.)
(E-3) Aramid fiber: φ0.50 × 20 mm (manufactured by Teijin Products)
(F) Resin (F-1) Resin containing a polymer of an acrylate ester;
Acrylic resin (manufactured by Nippon Synthetic Chemical Industry)
(F-2) a resin containing a copolymer of acrylic acid ester and styrene;
Acrylic / styrene resin (manufactured by Nippon Synthetic Chemical Industry)
(F-3) Styrene-butadiene resin (manufactured by Taiheiyo Materials Co., Ltd.)
(G) Water: Tap water (H) Fine aggregate: River sand (from Yuki, Ibaraki Prefecture)
(I) Coarse aggregate: Crushed stone (Sano, Tochigi Prefecture)

2. Test method (flow value, setting time, compressive strength, workability)
Using the above materials, mortar was prepared according to the formulation shown in Table 1 below. A Hobart mixer was used as the kneader.
Moreover, each physical property such as compressive strength was measured according to JIS shown below. Table 2 shows the results of (1) to (4).
(1) Flow value A flow value was measured in accordance with JIS A 5201 “Cement physical test method 11. Flow test” except that the falling motion was not performed 15 times.
(2) Setting time Setting time was measured according to JIS A5201 “Physical test method of cement”.
(3) Compressive strength According to JIS A 5201 "Cement physical test method", the compressive strength at the age of 3 hours was measured.
(4) Workability A case where no bleeding occurred was indicated by “◎”, a case where slight bleeding occurred was indicated by “◯”, and a case where a large amount occurred was indicated by “Δ”.

From Table 2, the mortar (Examples 1 and 2) using the acrylic / styrene resin and the acrylic resin of the present invention is a mortar containing no resin (Comparative Example 1) or a mortar containing a styrene / butadiene resin (Comparison) The following can be said compared to Example 2).
(1) Flow value The flow value of Examples 1 and 2 (about 180 mm) is higher than that of Comparative Example 2 (about 165 mm) and is equivalent to Comparative Example 1 that does not contain resin. Therefore, the mortar of the present invention is excellent in fluidity.
(2) Setting time The setting time of Examples 1 and 2 is shorter than Comparative Example 2 (starting time: 81 minutes, closing time: 108 minutes) for both the first start (about 50 minutes) and the end time (about 80 minutes), and does not contain resin. It is a value close to Comparative Example 1 (start: 34 minutes, end: 59 minutes). Therefore, the mortar of the present invention has little influence of the resin on the setting.
(3) Compressive strength The compressive strength (about 15 N / mm ² ) at the age of 3 hours of Examples 1 and ^{2 is} higher than that of Comparative Example 1 (about 12 N / mm ² ) and Comparative Example 2 (about 11 N / mm ² ). high. Therefore, the mortar of the present invention is excellent in strength development in a short time.
(4) Workability In Example 1, bleeding did not occur, and in Example 2, it occurred only slightly. In contrast, Comparative Example 2 has a large amount of bleeding. Therefore, the mortar of the present invention has excellent workability because there is little or no material separation.

3. Test method (slump, compressive strength, static elastic modulus, bending strength, bending toughness factor)
Concrete was prepared using the materials described above according to the formulation shown in Table 3 below. In addition, the kneading machine used the horizontal biaxial mixer.
Moreover, each physical property such as compressive strength was measured according to JIS shown below. Table 4 shows the results of (1) to (3).
(1) Slump Measured according to JIS A 1101 “Method for testing slump of concrete”.
(2) Compressive strength and static elastic modulus Compressive strength at a material age of 3 hours, 1 day, and 7 days was measured in accordance with JIS A 1108 "Method for testing compressive strength of concrete" using a summit mold of φ100 × 200 mm. Further, according to JIS A 1149 “Testing Method for Static Elastic Modulus of Concrete”, the static elastic modulus at the age of 1 day and 7 days was measured.
(3) Bending strength and bending toughness coefficient JIS A 1106 “Bending strength test method for concrete” and JIS A-G552-2010 “Bending strength and bending of steel fiber reinforced concrete using a steel mold of 100 × 100 × 400 mm According to the “toughness test method (draft)”, the bending strength and the bending toughness coefficient at the age of 1 day and 7 days were measured, respectively.

From Table 4, the following can be said about the concrete (Examples 3-5) of this invention compared with the concrete (Comparative Example 3) which does not contain a fiber, and the concrete (Comparative Examples 4 and 5) containing a steel fiber.
(1) Slump Slumps (8.0 to 12 cm) of Examples 3 to 5 are relatively larger than Comparative Example 4 (6 cm) and Comparative Example 5 (8 cm) containing steel fibers, and have good workability and the like.
(2) Strength The compressive strength (24.3 to 25.0 N / mm ² ) at the age of 3 hours in Examples 3 to 5 satisfies 24 N / mm ² or more specified in the manual, and is excellent in rapid hardening. Yes.
Moreover, since the bending strength of Examples 3-5 is equivalent to the comparative examples 4 and 5 containing a steel fiber, together with being lightweight, the concrete of this invention is more useful than the concrete containing a steel fiber. It can be said.

4). Other (waterproof)
The concrete of Example 5 was molded using a φ150 × 300 mm mold, and then cured in air at 20 ° C. for 7 days to prepare a φ150 × 300 mm specimen. Next, the specimen was divided into three equal parts in the height direction to prepare specimens having a diameter of 150 mm × 100 mm. Furthermore, after adhering a plastic pipe of φ18 × 350 mm with an epoxy adhesive near the center of the upper surface of the specimen, water was poured into the plastic pipe to a height of 300 mm. Moreover, after water injection, evaporation of water was prevented by covering the opening of the plastic tube with vinyl.
Nine days after the water injection, the height at which the water level of the plastic pipe decreased was measured, and the amount of water penetrating into the hardened concrete was calculated.
For comparison, except for removing the resin from the concrete of Example 5, the same test was performed on the concrete having the same blending ratio, and the amount of water penetrating into the hardened concrete was measured.
As a result, in the concrete of Example 5, the amount of permeated water was 7.5 mm ³ / min. On the other hand, in the comparative concrete containing no resin, the amount of permeated water was 10.8 mm ³ / min.
From the above results, if the quick-curing composition of the present invention is used, highly waterproof concrete or the like can be produced.

Claims (4)

The quick-hardening composition containing the following (A)-(G) component.
(A) A fast-setting admixture containing at least one inorganic salt selected from alkali metal carbonates, alkali metal sulfates, alkaline earth metal carbonates, and alkaline earth metal sulfates, and calcium aluminates (B) Portland cement (C) Setting modifier (D) Water reducing agent (E) Organic fiber (F) Resin containing a polymer of acrylic ester and / or resin containing a copolymer of acrylic ester and styrene (G )water   Furthermore, the quick-hardening composition of Claim 1 containing an antifoamer and / or a shrinkage | contraction reducer.   The mortar containing the quick-hardening composition of any one of Claim 1 or 2, and a fine aggregate.   Concrete containing the mortar according to claim 3 and coarse aggregate.